We have continued to study how therapeutic intervention affects coronary atherosclerosis in cynomolgus monkeys (M. fascicularis). We have determined their acceptance of and tolerance to semipurified diets, the response of their plasma lipids to different levels of dietary cholesterol, and the extent of coronary and aortic altherosclerosis after 6 months on a high cholesterol diet (baseline group). In experiements to determine how rice, wheat, and soya brans, chloestyramine, and alfalfa affect plasma lipids in cholesterol-fed monkeys, we found that only cholestyramine and alfalfa lowered plasma cholesterol. Currently, we are studying the effect of alfalfa, D-thyroxine, cholestyramine, Wy-14-643, and metformin on plasma levels of cholesterol, phospholipids, and triglycerides, as well as on established coronary atherosclerosis in monkeys. BIBLIOGRAPHIC REFERENCES: Malinow, M.R., P. McLaughlin, and L. Papworth. A model for therapeutic interventions on established coronary atherosclerosis in a nonhuman primate. Proc. First Brook Lodge Symposium on Anti-Atherosclerosis Drug Discovery, Augusta, Mich. 1975. Adv. Exp. Med. Biol. Plenum Press, New York, in press. Malinow, M.R., P. McLaughlin, L. Papworth, H.K. Naito, and L. Lewis. Failure of bran to affect plasma lipids in chlesterol-fed monkeys. Circulation 52:83, 1975. (Abstract)